All samples (feed, different tissues
of chicken and manure) were freeze-dried in freeze-drying system (Make) up
to a constant weight. The dried samples were ground in vibrational agate ball mill
for 5 min using a power of 60%. The powdered samples were sieved through nylon
sieve to obtain particle size [ø] 125 lm and were stored in closed polyethylene bottles
and kept in a refrigerator at 18 C until analysis.